Angular anguarl queryParams未接收参数

navbar.component.html

<a *ngFor="let item of studentClasses" routerLink="/classes/all-courses/, {queryParams: {prop: item.className}}">

所有课程.组件.ts

export const routes: Routes = [
  {
    path: 'all-courses/:className',
    component: AllCoursesComponent
  },
]

ngOnInit() {
    this.activeRoute.queryParams.subscribe(queryParam => {
      console.log(queryParam);
      // here I'm receving empty object. But I'm expecting to receive className
    });
}

您可以如下设置查询参数和片段：
`
链接到用户组件
`
RouterLink将使用这些链接生成此链接：
`/用户/bob？调试=true`
`构造函数（专用路由：ActivatedRoute）{}`
`恩戈尼尼特（）{
this.route.queryParamMap
.map（（params:params）=>params.params）
.订阅（（参数）=>{
if（params&¶ms['test']）{
设testQueryParamVal=params['test']；
}
});
}`

在组件中导入ActivateRoute和Router模块，并将它们注入构造函数中

import { ActivatedRoute, Router } from '@angular/router'

contructor(private route: ActivatedRoute, private router: Router){ ... }
Subscribe the ActivateRoute to the ngOnInit

ngOnInit() {

    this.route.queryParams.subscribe(params => {
      console.log(params);

    })
}

import { ActivatedRoute, Router } from '@angular/router'

contructor(private route: ActivatedRoute, private router: Router){ ... }
Subscribe the ActivateRoute to the ngOnInit

ngOnInit() {

    this.route.queryParams.subscribe(params => {
      console.log(params);

    })
}